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Video: What is a pulsar?

Hear the word “pulsar” and wonder what it is? Take 95 seconds to watch this video from NASA Astrophysics.

A pulsar is a rapidly spinning neutron star which is the small, incredibly dense remnant of much more massive star. How dense? A teaspoon of matter from a neutron star weighs as much as Mount Everest. A neutron star containing more matter than our sun would be only about 15 miles across.